Detection: Create local admin accounts using net exe

REMOVED DETECTION

This detection has been removed from the Splunk Threat Research content library and is no longer maintained or supported.

Reason: Renamed and updated logic

Removed in version: 5.2.0

Replacement: Windows Create Local Administrator Account Via Net

If you have any questions or concerns, please reach out to us at research@splunk.com.

Description

The following analytic has been deprecated. The following analytic detects the creation of local administrator accounts using the net.exe command. It leverages Endpoint Detection and Response (EDR) data to identify processes named net.exe or net1.exe with the "/add" parameter and keywords related to administrator accounts. This activity is significant as it may indicate an attacker attempting to gain persistent access or escalate privileges. If confirmed malicious, this could lead to unauthorized access, data theft, or further system compromise. Review the process details, user context, and related artifacts to determine the legitimacy of the activity.

1
2| tstats `security_content_summariesonly` count values(Processes.user) as user values(Processes.parent_process) as parent_process values(parent_process_name) as parent_process_name min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_net` AND Processes.process=*/add* AND (Processes.process=*administrators* OR Processes.process=*administratoren* OR Processes.process=*administrateurs* OR Processes.process=*administrador* OR Processes.process=*amministratori* OR Processes.process=*administratorer* OR Processes.process=*Rendszergazda* OR Processes.process=*Администратор* OR Processes.process=*Administratör*) by Processes.process Processes.process_name Processes.parent_process_name Processes.dest Processes.user
3| `drop_dm_object_name(Processes)` 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `create_local_admin_accounts_using_net_exe_filter`

Data Source

Name Platform Sourcetype Source
Sysmon EventID 1 Windows icon Windows 'XmlWinEventLog' 'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'
Windows Event Log Security 4688 Windows icon Windows 'XmlWinEventLog' 'XmlWinEventLog:Security'
CrowdStrike ProcessRollup2 Other 'crowdstrike:events:sensor' 'crowdstrike'

Macros Used

Name Value
security_content_summariesonly summariesonly=summariesonly_config allow_old_summaries=oldsummaries_config fillnull_value=fillnull_config``
create_local_admin_accounts_using_net_exe_filter ``
create_local_admin_accounts_using_net_exe_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK
+ Kill Chain Phases
+ NIST
+ CIS
- Threat Actors
ID Technique Tactic
T1136.001 Local Account Persistence

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting Value
Disabled true
Cron Schedule N/A
Earliest Time N/A
Latest Time N/A
Schedule Window N/A
Creates Finding (Notable) No
Creates Intermediate Finding (Risk Event) No
TTP detections generate a Finding (Notable) and may generate Intermediate Findings (Risk Events) for associated entities.

Implementation

The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the Processes node of the Endpoint data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.

Known False Positives

Administrators often leverage net.exe to create admin accounts.

Associated Analytic Story

Detection Testing

Test Type Status Dataset Source Sourcetype
Validation Not Applicable N/A N/A N/A
Unit Not Applicable N/A N/A N/A
Integration Not Applicable N/A N/A N/A

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range


Source: GitHub |

Version: 17